Fix minification

webpack.config.js

@@ -257,15 +257,15 @@ if (NODE_ENV !== "production") {
   config.output.devtoolModuleFilenameTemplate = "[absolute-resource-path]";
   config.output.pathinfo = true;
 } else {
+  // this is required to ensure we don't minify Chevrotain token identifiers
+  // https://github.com/SAP/chevrotain/tree/master/examples/parser/minification
+  const tokens = allTokens.map(currTok => chevrotain.tokenName(currTok));
   config.plugins.push(
     new UglifyJSPlugin({
+      test: /\.jsx?($|\?)/i,
       uglifyOptions: {
         mangle: {
-          // this is required to ensure we don't minify Chevrotain token identifiers
-          // https://github.com/SAP/chevrotain/tree/master/examples/parser/minification
-          except: allTokens.map(function(currTok) {
-            return chevrotain.tokenName(currTok);
-          }),
+          reserved: tokens,
         },
       },
     })